I find it strange that this latest info. was kept away from the public all this time. So Vanelli's car was there but he was at funeral.
Vanelli knew for certain that his life was in danger--if he didn't already know--after this botched murder attempt. Perhaps law enforcement didn't want to reveal the detail about his car's being parked near the Sinatra because the detail in some way gives clues about him and his routine that could be used by the people behind the murder plot.
The Loreto is a 45-minute walk from the cafe; so I doubt Vanelli walked there. Perhaps he got a ride to the Loreto from someone; and, again, that is a detail law enforcement may be reluctant to divulge.